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Old 02-12-2019, 11:09 PM   #1
snowball
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Alternator trouble

I've been chasing alternator gremlins for too long.

I just want my truck to run.

Looking at the diagram it looks like of I get a pigtail a connect the 2 wires to the positive I will get my truck running. Does anyone disagree with that?

I'll fix it properly when it warms up

Thank you
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Old 02-13-2019, 07:18 AM   #2
cadillac_al
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Re: Alternator trouble

One of those wires has to go to a key on source. If your wires are still there they should hopefully be hooked up where they are supposed to be.
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Old 02-13-2019, 09:59 AM   #3
snowball
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Re: Alternator trouble

Does it matter temporarily if they're not connected to the key source?

Wires are there. Just a break somewhere. I'll probably run new wires when I figure out how they're routed

What about the dash wire. I'm guessing I can leave it open...
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Old 02-13-2019, 10:03 AM   #4
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Re: Alternator trouble

Running the rust wire to the batt terminal on the alt gets close to the 1 wire alt setup. The brown wire needs to go to a switched power source as it will continue to draw power even when the alt isn't spinning.

If you have an idiot light instead of a gauge, make sure the bulb is good as a bad bulb can result in no alternator output.
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Old 03-01-2019, 11:53 AM   #5
snowball
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Re: Alternator trouble

So only running the rust wire will make it work for now?

I have both a gauge and an idiot light.
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Old 03-01-2019, 09:03 PM   #6
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Re: Alternator trouble

I'm confused as to what you think the issue is. You don't need an alt to make the engine run; you need one to power things and charge the battery after it's running.
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Old 03-04-2019, 10:40 AM   #7
snowball
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Re: Alternator trouble

I want to bypass the electrical connection to the alternator. I have a bad/loose wire and it keeps on turning off the alternator. I can see the idiot light coming on, and if I shake the wiring loom it goes off.

So if I buy a pigtail and wire it to the alternator https://www.ebay.com/p/Voltage-Regul...1369/215242723 and wire it to the alternator/batter so the alternator charges while it's running.

It's left me stranded before and I want it to stop until I sort out the wires.

Also, since it sounds like you've done this before, where do the rust and red wires go to? I'm guessing the red goes to the starter red wire...
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Old 03-06-2019, 10:12 AM   #8
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Re: Alternator trouble

This is a pretty easy thing to wire. The red from the post goes to the battery or starter positive post, the plug in has 2 wires usually red and white or red and brown, the red one goes to the post on the alt that has power feed. The white or brown one goes to a key switched power with a bulb in line. you can put the bulb anywhere being this is a temporary repair.
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Old 03-06-2019, 10:16 AM   #9
snowball
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Re: Alternator trouble

Gotcha.

So since it's a temporary, do I need a switched power and bulb?

If I just wire it to the alternator can I call it done until summer?
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Old 03-06-2019, 10:29 AM   #10
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Re: Alternator trouble

Brown wire has to be switched. It will draw power all the time while the alt is NOT spinning.

Think of the brown wire as a "starter" circuit for the alt. Power goes in when the alt isn't spinning. The bulb keeps the brown wire from back feeding enough current to power the ignition coil when the key is switched off.
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Old 03-06-2019, 10:36 AM   #11
snowball
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Re: Alternator trouble

I follow. So, where does the brown wire lead to? might be best just to rewire.

Or is there another more convenient place to get a switched source.
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Old 03-06-2019, 10:55 AM   #12
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Re: Alternator trouble

it needs to be switched and a bulb in circuit otherwise it will back feed and the engine will stay running
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Old 03-06-2019, 10:56 AM   #13
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Re: Alternator trouble

Yeah. Just wondering where the switched connection is located so I can rewire it.
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Old 03-06-2019, 07:05 PM   #14
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Re: Alternator trouble

As a temporary measure, the power wire for the HEI is switched. Just make sure the bulb is between the dizzy and alt otherwise the alt might keep powering the dizzy even with the ignition off. Not recommended for long term use.
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